Description of technical content: An air-cooled structure on a water pump is characterized by: including a water pump, the water pump includes a pump body and a motor, the motor includes a first shell, stator and rotor arranged in the first shell, a number of heat sinks are arranged on the outer surface of the first shell, and a circumference is arranged on the outer surface of the first shell. A number of supporting plates are surrounded by a second shell. The inner wall of the second shell, the outer surface of the first shell and several supporting plates form a number of air-cooling channels together. The rotor shaft of the rotor is fixed with a wind blade, which is located at the tail of the motor; and the top surface of the second shell is provided with a capacitive groove for electricity. The road control device is arranged in the holding groove, and a top cover is arranged on the holding groove; the front end of the second housing is provided with a front cover, and the rear end is provided with a rear cover; the front cover is provided with a number of air outlets, and the rear cover is provided with a number of air inlets, and the air inlets, air cooling channels and air outlets are connected with each other.